The All-Electric Home: Planning Your Switch Off Gas Without Blowing Up Your Switchboard

Can your switchboard handle an all-electric home? Often not without some planning. Going all-electric replaces three gas appliances with three serious electrical loads, and homes that swap them one at a time with no endpoint in mind are the ones that hit capacity problems halfway through. Plan the finished picture first and the whole transition gets cheaper, faster and safer.

1. What actually replaces gas

An all-electric home swaps out three workhorses. Gas hot water becomes a heat pump hot water system, which needs its own circuit and a tariff decision. The gas cooktop becomes induction, which needs a properly sized dedicated circuit; our guide to getting your switchboard induction ready covers that swap in detail. Gas heaters give way to reverse cycle air conditioning, and if you are considering a large ducted system, the three phase question for ducted aircon deserves an early look.

Each change is routine on its own. The catch is what they add up to.

2. The one-at-a-time trap

Most households electrify reactively: the gas hot water dies, a heat pump goes in. A year later the cooktop follows, then a heatwave sells the ducted aircon. Each installer checks only their own appliance, and nobody owns the total picture.

The result shows up late: no spare ways on the board for the induction circuit, or an aircon quote that collapses because the supply is already full. Fixing capacity mid transition is always dearer than planning for it up front, a point our renovation decisions guide makes about building works generally, and the same whole-of-home thinking is what our new build electrical checklist applies at the design stage rather than during a retrofit.

3. Start at the switchboard, not the appliance shop

Before pricing a single appliance, get the board assessed. Three questions decide the plan: Is the board itself modern and safe, or is it an old fuse box that needs replacing anyway? How many spare ways are left for new circuits? And what is the supply actually rated at?

If the board needs upgrading, do it first and size it for the finished home, not the current one. Our switchboard upgrade guide covers what that involves.

4. Add up the demand before you commit

The whole transition turns on one number: the maximum demand of the finished, all-electric home. The calculator embedded on this page gives you a first estimate, and our companion post on maximum demand and spare capacity explains how to read the result.

Two things follow from that number. If the finished load fits your existing supply, you can sequence the swaps freely. If it does not, you know now, while there is still time to choose between load management, tariff timing and a supply upgrade. Significant load increases can also mean a Notification of Service Work with Ausgrid or Endeavour Energy, and you can check your network area in seconds with our postcode checker.

5. Decide the phase question once

Some all-electric homes need three phase power. Many do not. It depends on the size of the home, the aircon choice, EV plans and how loads are timed. What hurts is answering it twice: electrifying on single phase, then discovering the ducted system or a 22kW EV charger needs a three phase upgrade after all.

Make the call early with our single vs three phase decision guide, and see what changes in a three phase upgrade if the answer is yes. Doing the upgrade once, before the appliance swaps, beats retrofitting it into a half finished plan.

6. Get the tariff right as you go

All-electric homes shift more of the bill onto electricity, so the tariff matters more. Hot water belongs on controlled load or a timed circuit, flexible loads belong in the off peak windows, and the metering to support that is part of the electrical work, not an afterthought. Our smart meter upgrade team handles that alongside the circuits. If you're also weighing up battery storage to soften the shift onto electricity, our battery ready checklist covers the wiring and switchboard provisions worth doing at the same time as the rest of the electrification work. Eligible seniors should also check the NSW seniors energy rebate before locking in a tariff plan.

7. Sequence the gas exit properly

The electrical work and the gas work are separate trades. The clean order: electrical capacity confirmed first, new circuits and appliances in second, and the gas capped off by a licensed gasfitter once nothing depends on it. Running both fuels indefinitely means paying two supply charges, which is one of the quiet costs our heat pump vs gas comparison weighs up.

More on three-phase and power supply upgrades

• Power supply upgrades: is your home smart-home ready?
• Planning a home renovation? Don't forget to upgrade your power supply
• 3 phase power upgrade cost Sydney: the 2026 homeowner's guide
• 200A three phase supply in Sydney: when you need it and how to get it approved
• 400A three phase supply in Sydney: the full upgrade process
• Over 100A three phase in Sydney: the Ausgrid approval process
• Over 100A three phase in Sydney: the Endeavour Energy approval process
• Power supply upgrades explained: are your appliances ready for the modern world?

How High Demand Electrical helps

We do the part nobody else quotes: the whole-of-home plan. That means a site assessment of your board, supply and mains, a maximum demand calculation for the finished home, a clear answer on the phase question, and the circuits, board work and metering staged into as few visits as possible. If a supply upgrade is needed, we are Level 2 ASP accredited on both Sydney networks, so the network application and connection work stay in house.

Plan the switch properly

Get a power supply and switchboard assessment quote or call 0402 559 777 and we will map your all-electric plan. Every job starts with a site assessment before scope and pricing are confirmed.